Mechanism for drawing metal



May 23,193. J. T. LEECH MECHANISM FOR DRAWING METAL Filed Dec. 28 1927 5Sheets-Sheet 1 INVENTO R 0% fil oq wi May 23, 1933. J. T. LEECHMECHANISM FOR DRAWING METAL Filed Dec. 28, 1927 5 Sheets-Sheet 2 lg/ENTW May 23, 1933. J. 'r. LEECH MECHANISM FOR DRAWING METAL INVENTOR QmwmNN

May 23, 1933.

J. "r. LEECH 1,911,157

MECHANISM FOR DRAWING METAL Filed Dec. 5 Sheets-Shet 4 IHH 52 INVE May23, 1933. J. "r. LEECH MECHANISM FOR DRAWING METAL 5 Sheets-Sheet 5lgENTOR 4 A 1/; w M 4 9 M Filed Dec. 28, 1927 Patented May 23, 1933UNITED STATES PATENT OFFICE COMPANY, 01' BEAVER FALLS, PENNSYLVANIA, ACORPORATION OF PENNSYL- VAN IA MECHANISM FOR DRAWING METAL Applicationfiled December 28,1927. Serial No. 243,100.

grasped by a suitable clamp. In the draw-- ing of long or continuouslengths of stock, the end of the material which is pushed through thedie is engaged by a gripping device on a revolving drum. As the drumrevolves, the stock is pulled through the die and reduced by the die tothe proper shape and size, and the surface of the material is finished.Due to the strain which the material is under in being pulled throughthe die and around the drum, the wire is stretched unequally. Thesurface of the wire lying on the drum is curved on a shorter radius thanthe portion of the wire at the outside of the drum. The difference inthe radius of ourvature is, of course, equal to the diameter of thewire. For instance, in the drawing of -inch wire there would be adifi'erence of inch in the radius of curvature. This difference in theradius of curvature stretches the metal unequally and makes it difiicultto straighten the wire. The only type of straightening machine which hasbeen developed for straightening wire which has been drawn on a drum isone which necessitates the wasting of several feet of wire on eachlength. Also, when the wire under tension is wound on the drum, oneconvolution will overlap and slip over another, and the metal is damagedthereby.

Not only is the metal stretched unequally in being pulled on to a drumand damaged by the contact of the metal with adjacent convolutions, butconsiderable time is lost in removing the coiled material from the drum.During the time that the material is being removed from the drum thedrawing machine is inoperative.

][n the drawing of short lengths of bars the stock is pushed through adie and engaged in a gripping device which travels longitudinally alongthe drawing machine a distance equal to the length of the bar beingdrawn. When the gripping device has travelled the full length of thebar, the gripping jaws must be opened, the bar discharged, and thegripping device returned to the forward end of the machine to grip thenext piece of material to be drawn. Considerable time is lost inreturning the gripping device to operative position after it hastravelled the full length of the bar in one direction. Considerabledifficulty is also encountered in releasing the jaws of the grippingdevice after the bar has been pulled. The time required for releasingthe gripping jaws of the gripping device and the time required forreturning the gripping device to operative position for releasing thejaw constitutes a considerable portion of the operating time of thedrawing machine.

The present invention providesa dra ing mechanism applicable to thedrawing of either continuous strips of wire or to the drawing of barlengths wherein a drum about which the wire is coiled is not required,and wherein there is no time loss due to the releasing of the grippingjaws and the returning of the drawhead to starting position.

According to my invention there is provided a draw frame having acontinuous chain therein with a plurality of cross heads thereon. Eachcross head is provided with wire gripping means of unique constructionand so arranged that when one draw head is at the extreme limit of itsoperating travel another draw head will be in operating position. Thedraw heads automatically release the wire or bars at the end of theoperating travel and can be arranged to automatically engage the wire atthe starting point of their operating travel.

My invention may be readily understood by reference to the accompanyingdrawings, which illustrate a preferred embodiment of my invention, andin which Figure 1 is a side elevation of a drawing machine constructedin accordance with my invention;

Figure 2 is atop plan view partly broken away of the machine shown inFigure 1;

Figure 2-A is a top plan view of the left JACOB T. LEECH, OI BEAVER,PENNSYLVANIA, ASSIGNOR TO IJ'NION DRAVN STEEL hand end portion of Figure2, showing the driving connection for the pusher mecha-.

nism;

Figure 3 is a side elevation on a larger scale of the front end of themachine with the pusher mechanism removed therefrom;

Figure 4 is a side elevation on a larger scale of the rear end of themachine;

Figure 5 is a plan view of one of the gripping heads;

Figure 6 is a side elevation of the gripping head shown in Figure 5;

Figure 7 is an end view of the gripping head shown in Figure 5;

Figure 8 is a cross section in the plane of line VIII-VIII of Figure 5;

Figure 9 is a cross section in the plane of line IXIX of Figure 6;

Figure 10 is a plan View of one of the gripper jaws;

Figure 11 is a cross section along the line XI-XI of Figure 10 Figure 12is a detail view of one of the iongitudinal wedges;

Figure 13 is a cross section along the line XIIIXIII of Figure12;

Figures 14 and 15 are detail views showing one of the vertically movablewedges for cooperation with the wedge shown in Figure 12;

Figure 16 is a detail view of one of the links connecting the gripperhead to the draw chain; and

Figure 17 is a perspective view of one of the bearing blocks for thelink of Figure 16.

The drawing mechanism as shown in F igure 1 comprises a front endhousing 2, a rear end housing 3 and a bed frame 4 sup ported on thehousings 2 and 3.

Supported in hearings in the front end housing 2 is a transverse shaft 5having spaced apart sprocket wheels 6 thereon. Supported inlongitudinally adjustable bearings 7 in the rear end housing 3 is atransversely extending shaft 8 having sprocket wheels 9 thereon. Passingaround the sprockets 6 and 9 are continuous parallel roller chains 10.

In the front part 11 of the front frame 2 is a drawing die 12. Mountedin a guide way on the front of the part 11 of the front frame 2 forvertical movement thereon is a pusher mechanism 13. The pusher mechanism13 may be of any suitable preferred construction. The particularmechanism which is shown is fully described in my co-pending applicationSerial No. 250,505, filed January 30, 1928. The pusher mechanism isdriven from the shaft 5 through a sprocket wheel 14 and a chain 15, thechain 15 being sufficiently slack to allow for a limited verticalmovement of the entire pusher unit.

The die 12 has its vertical center disposed substantially in line withthe center line of the upper reach of the chains 10.

Secured on the chains 10 at regular intervals are gripping heads 16, Asmany of these gripping heads may be used as are desirable. Ordinarily,three of the gripping heads are sufficient and but three of them areshown in the accompany drawings.

Each of the gripping heads comprises a main cross head 17 having a cutaway central portion 18. At each end of the member 17 is an elongatedboss or projection 19 having rounded ends. 19. In the cross member 17 ateach side of the cut away portion 18 is an opening 20. Received in eachof the openings 20 is a post 21 on which is a wedge 22, the wedge havingan upwardly extending projection 23. The upwardly extending projections23 are passed through keeper plates 24 secured to the top of the member17 at each side of the central cut away portion 18.

Received in the cut away portion 18 at each side thereof is a wedgeblock 25 having a Vertical face 26 and an inclined face 27, the inclinedface 27 being adapted to'cooperate with one of the tapered faces of thewedge block 22. The vertical face 26 of the block 25 is taperedlongitudinally, the wedge being wider at one end than at the other.

Located in the central opening 18 at each side thereof is a gripping jaw28 having a longitudinally tapered face 29 for cooperation with thetapered face 26 of the member 25. Each of the jaw members 28 has a wiregripping portion 30, the portions 30 of the two members 28 beingopposed. At each end of each member 28 is a transverse lug 31. The lugs31 extend in front of the wedge members 25 at each end thereof. Receivedin a pocket 32 in one end of each wedge 25 is a compression spring 33.The compression springs 33 engage against the lugs 31 of the respectivemembers 28 for urging the members 28 longitudinally with respect to themembers 25.

The gripping heads 16 are connected to the cross chains 10 by means ofspecial links 35 shown in detail in Figures 5 and 16, havinglongitudinally extending slot 36 therein. The link 35 is adapted to fitagainst one end of the cross head 16 with the boss 19 projecting intothe slot 36. At each end of the boss 19 is a bearing block 37 having acurved hearing surface for engaging with the rounded portion a of theboss. By reason of the slot 36 being longer than the boss 19 and byreason of the bearing blocks 37, the cross heads have a floatingconnection with the chain. Inasmuch as the chains will wear unevenly,and inasmuch as it is desired that the cross heads shall always be atright angles to the at one side of the machine.

bearing block 37 and the end of the slot 36 A shim of similar thicknesscan be inserted between the rear block and the end of the slot at theopposite side of the cross head. Such shims so disposed are shown at 38in Figure 5.

On the lower ends of the vertically movable bars 21 are cam engagingcaps 21. On the tops of the extensions 23 are similar ca 5 23.

n the front frame 2 between the sprocket wheels 6 is a bracket 39. Suported on a shaft 40 above the bracket 39 is a inged plate 41 having aslightly curved top face. On the under side of the plate 41 is aprojection 42 around which is a compression spring 43, the purpose ofthe compression spring being to urge the plate 41 upwardly to a verylimited extent. Means may be provided for rocking the plate from theoutside of the machine. Such means may comprise a lever 44 on the shaft40 having a laterally turned extension 45 projecting through a slot 46in the side of the housing.

In the operation of the machine, the chain is driven from a suitablesource of power. A driving means is diagrammatically indicated in Figure1, where 47 indicates a driving motor which drives asprocket 48 througha reducing gear 49. The sprocket 48 drives a sprocket 50 on the shaft 8.In first starting the machine the end of thewire or rod is drawn throughthe die 12 by means of the pusher mechanism 13. The end of the wire orrod projects through the die sufficiently to extend between the jaws 30of the gripping device 16, which is then located at the starting end ofthe machine, as shown in Figure 1. When the end of the rod or wire hasbeen projected through the die and is positioned between the jaws 30,the operator pushes down on the rod 45 of the lever 44 rocking the plate41 upwardly. At this time the caps 21 of the rods 21 are resting on theplate 41, so that the upward movement of the plate 41 serves to lift therods 21 vertically raising the wedges 22. The wedges 22 force the wedgeblocks 25 toward each other, moving the jaws 28 inwardly so that.

the gripping portions 30 of the jaws are in frictional contact with theend of the wire or rod. Then the chain is started. Due to the frictionwith which the jaws engage the rod, the jaws are moved longitudinally.The longitudinal movement of the jaws causes the tapered face 29 of thejaw blocks 28 to ride along the tapered faces 26 of the wedge blocks 25,thereby forcing the jaws into tight gripping engagement with the end ofthe rod or wire. As the chain continues to move glong the rod or wire ispulled through the When the gripping head 16 has moved along the entireupper reach of the conveyor to a point adjacent the sprocket wheels 9,the

caps 23 on the upper ends of the extension 23 will engage a curved camplate 52 This cam plate 52 will force the extensions 23 down, moving thewedge blocks 22 down. As soon as the wedges 22 move down the wedgeblocks 25 then spread apart and allow the jaws 28 to release the rod. Assoon as the aws 28 are released from the wire or rod, the compressionsprings 25 act to move the jaws 28 longitudinally to their normalinoperative position.

If a continuous length of wire is being drawn, the next cross head 16will have been moved to operative position just before the first crosshead releases the bar. The caps 21 riding up on the curved surface ofthe plate 41 will be lifted to automatically force the wedges 22 in toset the jaws 28 against the rod. By the time that the strain has beenreleased from. the first cross head, the second cross head will betightly gripped to the wire and continue to pull the same. The operationis repeated as long as the continuous length is being drawn through themill. It is only necessary to lift the plate 41 by operation of thehandle 46 at the start of the operation because at the start of theoperation the wire does no project sufiiciently far through the die toenable the jaws to grip it to start the pulling. The wire is thus drawnthrough the die continuously without being drawn over a drum and theline of pull is always a straight line. Uneven strains in the materialare thus avoided and the material is not damaged as it is where it iswound on a drum under heavy tension.

In the drawing of short lengths of rods the operation of the jaws is thesame. However, in the drawing of short lengths of rods it is necessaryto rock the plate 41 manually to set the jaws of the cross head for eachlength being' drawn. However, due to the fact that by the time onelength of rod has been drawn another cross head is in operatingposition, no time is lost in waiting for a cross head to be returned tothe starting point. There is always a cross head in position to take theend of the bar as it is pushed through the die, so that the machine canbe operated substantially continuously.

The construction of the jaws and wedges is such that just as soon as thewedges 22 are dropped down the entire gripping device can release itselffrom the wire or rod. Gripping devices as heretofore constructed requirethat the tension be relieved from the wire or red before the grippingdevice could be released. The present invention eliminates the time andlabor necessary for relieving the tension on the rod because it iscapable of releasing whether the rod is under tension or not.

Upon inspection of Figures 7 and 8, it will be seen that the boss orprojections 19 at each side of the cross head lie in the plane of theupper flight of the chain and that a horizontal line drawn centrallythrough the boss passes through the center of the gripping jaws 30. Thecenter of the ripping jaws is in the center of the axis of the drawingdie. Therefore, as the draw head moves along the bed of the machine, itis drawing the metal directly along the axis of the die. Due to themanner in which the draw head can be adjusted with respect to the twochains by shimming the blocks 37, any looseness which develops in thechains tending to throw the draw head out of a true transverse positioncan be easily compensated for.

The invention results in the saving of considerable time in the drawingof wire in long lengths or in the drawing of short bar lengths ofmaterial. In the former case, it eliminates the time required inremoving the wire from the drawing drums. In the latter case iteliminates the idle return travel of the draw head to operative positionas well as the operation of backing up the draw head to release thejaws. In the drawing of wire it results in an improved product because,when a wire is wound under the drawing tension over a drum, unequalstrains are developed in the portion of the metal nearest the surface ofthe drum and the peripheral portion. To straighten wire in which suchstra ns have developed requires an additional operation and one whichresults in the loss of a considerable amount of material due to the factthat any straightening machines which will satisfactorily straighten thewire require that a certain portion of the wire be mutilated. Also, whenthe wire is wound over a drum under drawing tension, one convolutionslipping on or over another multilates the wire. The straight linecontinuous pull developed by the present invention eliminates anyunequal tension in the metal as it is drawn and avoids mutilation byeliminating the winding of the wire under tension on a drum. In adrawing unit of the type herein disclosed, the wire may be wound on adrum after it has beendrawn, but the drum itself would not draw the wirethrough the die, and the wire would not be wound under such heavy tension as to set up unequal strains. lVhere the wire is to be cut intorodleng'ths, it can be fed directly from the drawing unit to a shearingunit, such as a flying shear, which will automatically cut the wire intostraight lengths. thereby eliminating entirely the expense ofstraightening operations now required.

lVhile I have shown and described a preferred embodiment of myinvention, it will be understood that this is merely illustrative of theinvention and that various changes and modifications may be made thereinwithin the contemplation of my invention and under the scope of thefollowing claims. It will also be understood that the; novel cross headconstruction herein disclosed is particularly applicable to use on acontinuous chain. It can be advantageously used in present types of drawheads and eliminate the necessity at the end of each draw of slightlybacking up the draw head to release the jaws before the wire can bereleased from the jaws and the draw head returned to its operatingposition.

y I claim: I

1. In an apparatus for making drawn steel, a drawing die, a frame, anendless carrier comprising continuously parallel chains on the frameoperating in the same plane, said carrier having a horizontal reachsubstantially in the plane of the axis of the die and substantiallyparallel with the axis of the die, a plurality of cross heads on thecarrier at spaced intervals therealong extending between the chains,said cross heads being adj ustably connected with the chains at eachside thereof through connectors which are variable relatively to thecross heads, and wire gripping jaws on the cross heads. and meanscarried by said frame adjacent the die end of the chain and operativelyassociated with said gripping jaws for moving the latter into grippingrelation to a Wire.

2. In an apparatus for making drawn steel, a drawing die, an endlesscarrier comprising continuously parallel chains disposed side by side,said carrier having a horizontal reach substantially in the plane of theaxis of the die and substantially parallel with the axis of the die, aplurality of cross heads on the carrier extending between the chains andarranged at regularly spaced intervals therealong, said cross headsbeing adjustably connected with the. chains at each side thereof, andwire gripping jaws on the cross heads. the center of the aws beingsubstantially coincident with the axis of the drawing die throughout thetravel of the cross heads along the said horizontal reach of the carrierand means carried by the cross heads for moving said jaws into operativeposition upon movement of said chains.

3. A draw head for drawing machines comprising a cross frame, workengaging jawsin the cross frame movable longitudinally, longitudinallymovable wedge elements carried by the cross frame and engageable withthe jaws for forcing the jaws toward each other upon longitudinalmovement of the cross frame in one direction, and vertically movablewedges arranged for cooperation with longitudinally movable wedges foralso moving the jaws toward and away from each other.

4. A wire gripping unit for metal drawing mechanism comprising a crossframe, a pair of longitudinally movable jaws on the cross frame.longitudinally tapered wedges for cooperation with the jaws, said wedgesbeing movable toward and away from each other, and movable means back ofthe Wedges movable transversely of the wedges for positively moving thewedges toward each other.

5. A wire gripping unit for metal drawing mechanism comprising a crossframe, longitudinally movable jaws on the frame, a transversely movablelongitudinally tapered wedge back of each jaw for cooperation therewith,and movable means back of the wedges movable transversely of the wedgesfor effecting transverse movement of said wedge.

6. A wire gripping unit for metal drawing mechanism comprising a crossframe, longitudinally movable work engaging jaws on the cross frame, atransversely movable longitudinally tapered wedge back of each jaw forcooperation therewith, means for effecting transverse movement of saidwedges toward each other, and a spring operatively engaging each jaw foropposing longitudinal movement thereof in one direction.

7. A wire gripping unit for. metal drawing mechanism comprising a crossframe, a pair of longitudinally movable jaws in the cross frame, atransversely movable longitudinally tapered wedge back of each jaw forcooperating therewith, and a second wedge back of the first and movabletransversely thereof and at right angles thereto, said second wedgesbeing adapted to effect transverse movement of said first wedges.

8. A wire gripping unit for metal drawing mechanism comprising a crossframe, a pair of longitudinally movable jaws in the cross frame, atransversely movable longitudinally tapered wedge back of each jaw forcooperating therewith, and a second wedge back of the first and movabletransversely thereof and at right angles thereto, said second wedgesbeing adapted to effect transverse movement of said first wedges, eachof said second wedges having an operating extension thereon.

9. A wire gripping unit for metal drawing mechanism comprising a crossframe, horizontally disposed longitudinally reciprocable jaws in saidcross frame, horizontally disposed transversely movable longitudinallytapered wedges back of the jaws for cooperation therewith, and avertically movable vertically tapered wedge back of each of saidhorizontally disposed wedges for effecting transverse movement thereof.

10. A draw head for drawing units comprising a cross frame, horizontallydisposed longitudinally reciprocable jaws in said cross frame,horizontally disposed transversely movable longitudinally tapered wedgesback of the jaws for cooperation therewith, and a vertically movablevertically tapered wedge back of each of said horizontally disposedwedges for effecting transverse movement thereof, each of said verticalwedges having an operating extension at the top and the bottom thereof.

movement thereof.

11. A draw head for drawing units comprising a frame, longitudinallymovable jaws in the frame, springs for yieldably resisting thelongitudinal movement of the jaws, a longitudinally tapered wedge backof each jaw for cooperation therewith, and means back of each wedge foreffecting transverse 12. An apparatus for themanufacture of drawn steel,a die, an endless carrier having a horizontal reach extending in thedirection of the axis of the die, a frame structure along which thecarrier moves, a draw head on the carrier having a pair oflongitudinally movable jaws therein, longitudinally tapered wedges backof the jaws for causing the jaws to move into gripping position uponlongitudinal movement of the jaws with respect thereto, other means foreffecting transverse movement of the jaws into and out of grippingposition, said means having an operating extension thereon, and means onthe frame for engaging said operating extension to actuate the crosshead.

13. An apparatus for the manufacture of drawn steel, a die, an endlesscarrier having a horizontal reach extending in the direction of the axisof the die, a frame structure along which the carrier moves, a draw headon the carrier having a pair of longitudinally -movable jaws therein,longitudinally tapered wedges back of the jaws for causing the jaws tomove into gripping position upon longitudinal movement of the jaws withrespect thereto, other means for effecting trans verse movement of thejaws into and out of gripping position, said means having an operatingextension thereon, means on the frame adjacent the die for cooperatingwith said extension to effect a closing movement of the jaws at thebeginning of the travel of the jaws along said horizontal reach of theconveyor, and other means adjacent the opposite end of said horizontalreach for cooperation with said operating extension to effect movementthereof in a reverse direction to permit spreading of the jaws.

14. In a drawing machine, a drawing die, an endless carrier having ahorizontal reach extending in the direction of the axis of the die andin substantially the plane thereof, a draw head on the carrier, a framefor the carrier, jaws on the draw head movable longitudinally thereof,longitudinally tapered wedges for cooperating with the jaws for forcingthe jaws toward each other upon longitudinal movement of the jaws in onedirection. a vertically extending wedge back of each of the jaws foralso moving the jaws toward and away from each other, means at one endof the frame adjacent the die for raising said vertical wedges to closethe jaws, and means at the opposite end of said car rier frame forlowering said vertical wedges to permit opening of the jaws.

15. In a mechanism for drawing metal, a die, a draw head, an endlesscarrier on which the draw head is mounted, a frame on WhlCh the endlesscarrier is supported, jaws in the draw head movable relatively theretotransversely and longitudinally with respect to their longitudinal axesinto and out of gripping position, means for effective transversemovement of the jaws comprising a vertically movable operating wedge, anoperating extension for said last named means, means at one end of saidframe for coopera tion with said operating extension adapted to set thejaws, and means at the other end of the frame for cooperating with saidoperating extension to release the jaws, both of said last named meansbeing disposed in the path of travel of said cross head.

16. An apparatus for the manufacture of drawn steel comprising a die, anendless chain located entirely at one side of the die having a reachwhich travels in a direction coaxially of the die and in the samehorizontal plane as the axis of the die, a series of cross heads carriedon the endless chain at regularly spaced intervals therealong, each ofthe cross heads of said series having a pair of oppositely movablecooperating gripping jaws thereon which are in the same plane as thechain, means for setting the jaws into gripping position at thebeginning of their travel along said reach, means operable upon furthermovement of the cross head for holding the jaws set during such travel,and means for releasing the jaws near the end of the travel of the crosshead along said reach. 1

17. In a drawing machine, a die, an endless carrier, means for drivingthe carrier continuously in one direction, a plurality of transversecross heads having a pair of movable opposed gripping jaws slidablymounted thereon, means carried by said carrier and engageable with saidgripping jaws adapted to move said jaws into operative position uponmovement of said carrier, and means for releasing both of said jaws ofthe cross heads when the cross heads have moved to a point remote fromthe die, the center of the carrier and gripping jaws being in the samehorizontal planeas the center of the die.

18. An apparatus for the manufacture of drawn steel comprising a die, anendless chain operatively disposed entirely on one side of the die andhaving a reach which travels in a direction co-axially of the die, meansfor driving the chain continuously in one direction, a series of drawheads carried on the endless chain, gripping jaws carried by said drawheads, means including wedge 19. An apparatus for the manufacture ofdrawn steel includin a die, a carrier including horizontally dlsposedendless chains parallel throughout the extent of their travel andpositioned entirely at one side of the die, one reach of the carrierextending substantially parallel to axis of the drawing die and in thehorizontal plane thereof, means for driving the carrier continuously inone direction, a plurality of draw heads on the carrier between thechains and arranged at widely separatedintervals therealoug, gripping'aws on said draw heads, and means carried by said carrier operable uponmovement of said chains for moving said gripping jaws into operativeposition.

20. In a wire drawing unit,'a die, a frame, an endless carrier includingspaced chains so arranged on the frame as to be parallel throughout theextent of their travel, said carrier having a horizontal reach extendingsubstantially parallel with the axis of the die and in the horizontalplane of the die, a draw head carried between the chains and havinggripping jaws thereon, means carried by said frame adjacent the die endof the chains and operatively associated said gripping jaws for movingthe latter into gripping relation to a wire upon movement of the endlesschain, the center of the gripping jaws of the draw heads beingcoincident with the axis of the die when the draw head is in onehorizontal reach of said carrier, means for driving the carrier in onedirection and fixed means remote from the die end of the frame andoperatively associated with the gripping jaws for releasing the grippingpressure of the latter on the wire.

In testimony whereof I have hereunto set my hand.

JACOB T. LEECH.

members adapted to move said gripping jaws into operative position uponmovement of said endless chain, said draw heads being spaced atsubstantial intervals along the chain.

